Wiring harnesses comprise leads of insulated electrical wire having one or more ends terminating in a multiple lead terminal or terminals and are widely used in many different types of electrical and electronic apparatus. For example, Folk U.S. Pat. No. 3,875,662 and Folk, et al. Pat. No. 4,043,017 show differing wiring harness manufacturing apparatus for automatically inserting the leads into terminals.
In this type of apparatus, it is known to grip and advance the leads toward a terminal, and to automatically insert the leads into the terminal. Also, at some time in the process the leads are automatically severed away from the main supply of lead wire material, for example spools of coiled electrical wire.
In prior apparatus designs, certain disadvantages have existed. As the leads are clamped and advanced toward engagement with a terminal, it is desirable for the leads to be held under a predetermined tension as they are advanced. However, a simple bar clamp or the like may not provide precise enough tension on the individual leads, because the individual diameters of the respective leads may be variable. The result of this may be that one lead of reduced diameter slides almost freely without tension, while another lead in the same group, having a larger diameter, is very tightly clamped. This can result in malfunctions of the process, and a significant amount of failure of production of wiring harnesses.
Also, as the leads are clamped and advanced, a forward end portion of each lead must project from the clamp to permit its engagement with the terminal. However, these projecting ends can frequently twist and bend, due for example to the elastic memory of their insulating coatings, with the result that in prior art machines, failures of the lead ends to properly engage with the terminal are a significant possibility.
By this invention, the problem can be eliminated by means of a retractable guide plate as described above.
Furthermore, means are provided in the device of this invention for causing the apparatus to manufacture wiring harnesses in which the individual leads may be of differing lengths. The individual pattern of the differing lengths may be easily changed, with relatively minor adjustment of the apparatus.
Likewise, other functional improvements and efficiencies of operation are provided by the device of this invention.